Valve-gear for steam-engines



(No Model.)

" D. CLARK &. T. G. BLATOH. VALVE GEAR FOR STEAM ENGINES.

Patented May 1,1883.

INVENTORV:

@129, awe/n ATTORNEYS.

a-Lithognphan Washington, a. c.

UNITED STATES.

PATENT OFFICE.

DAVID CLARK AND THOMAS G. BLATOH, OF HAZLETON, PENNSYLVANIA.

VALVE-GEAR FOR STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent NO. 276,773, dated May 1, 1883.

Application filed February 20, 1883.

To all whom it may concern:

Be it known that we, DAVID CLARK and THOMAS G. BLATOH, both of Hazleton, in the county of Luzerne and State of Pennsylvania,

have invented a new and Improved Valve- Gear for Steam-Engines, of which the following is a full,clear, and exact description.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similar letters. of reference indicate corresponding parts in all the figures.

Figure 1 is a side elevation of our improvement, the engine, cylinder, and driving-shaft being shown in section. vation of the rock-arms and their pivotingshaft, part being broken away. Fig. 3 is a plan viewof the link and slide-block connected with the link-motion rock-arms.

The object of this invention is to provide a mechanism by means of which the expansion of steam can be controlled by the engineer while the engine is in motion and without shortening the stroke of the slide-valve, and thus without obstructing the free entrance and exit of the steam. Upon the vibrating link is placed a slide-block connected with the cut-off valve, so that the said cut-oft valve will be operated from the said link. With the slide-block are connected. rock-arms and connecting'rods, whereby the said slide-block can be readily adjusted to regulate the movements of the cut-off valve, as will be hereinafter fully described.

A represents a steam-cylinder. B is the slide-valve, and C is the cut-off valve sliding upon the top of the slide-valve'B.

To the slide-valve B is attached the end of the main valve-rod D, the other end of which is pivoted to the main rock-arms E, connected with the ordinary link-motion, F, and operated by the eccentrics G H from the drive-shaft I. The link-motionF is adjusted to regulate the stroke of the valve B and the point at which the steam is cut off by means of the rockarms J, connected by a bar, K, with the said link-motion, and by a rod, L, with a lever on the engine,which lever is not shown in the drawings.

Fig. 2 is a rear ele'.

(No model.)

To the cut-0d valve 0 is attached the end of the valve-rod M, which is 'jointed and is pivoted at its other end to the block N, which slides upon the vibrating link 0. One end of the link 0 is pivoted to the main rock-armsE or to the main valve rod D, so as in either case to be connected with and receive its motion fromthe said main rock-arms E. The other end (if the link 0 is connected by a rod, 1?, with intermediate'rock-arms, Q, which are connected with and operated by a separate eccentric, R, placed upon the drive-shaft I.

The slide-block N is connected by a bar, S, with rock-arms T, which are connected by a rod, U, with a lever on the engine, which lever is not shown in the drawings, so that theengineer, While the engine is in motion, can opcrate the rock-arms T and adjust the slideblock N upon the link 0. With this construction, whenthe slide-block N is lowered to its lowest point upon the link 0, the cut-off valve 0 will be at rest upon the center of the valve B, causing no friction and leaving the ports of the said valve B uncovered,so that the entrance and exit of the steam will be wholly controlled by the said valve B. When the slide-block N is raised upon the link 0 it gives motion to the cut-off valve 0 in the opposite direction from the valve B and cuts ofi' the steam at different points of the stroke of the piston, according as the said slide-block N is raised more or less.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is-

Invalve-gear for steam-engines, the combination, with the slide and cut-oft valves B 0,

main valve-rod D, main rock-arms E, linkmotion F, and drive-shaft eccentrics G H, of

the slide-block N, link 0, rock-arms Q T, eccentric R, and rods S U, whereby the steam expansion may be controlled by the engineer,

as described.

DAVID CLARK. THOMAS G. 'BLATOH. Witnesses:

. JOHN A. BARTON,

G. BAOHMAN. 

